This invention relates in general to communications, and more particularly to a protocol converter apparatus and method.
A communications system includes a collection of interconnected devices. Often these devices communicate data using different protocols. For example, a remote that communicates data in a first protocol may desire to access a host that communicates data in a second protocol. A protocol converter may be used to allow communications between the remote and the host.
As communications systems become larger and more complex to serve a variety of devices, protocol converters should adapt to service an ever-increasing number of communications protocols. Hardware-based protocol converters are difficult to adapt to service new protocols. Current software-based protocol converters often suffer from a lack of modular design, an inflexible and unreliable hardware/software interface, and an inability to adapt quickly and efficiently to new and changing communications protocols.
In accordance with the present invention, the disadvantages and problems associated with protocol converters in a communications system have been substantially reduced or eliminated.
In accordance with one embodiment of the present invention, a communications system includes a remote that transmits first data in a first protocol and a host that receives second data in a second protocol. A protocol converter coupled to the remote and the host receives first data from the remote. The protocol converter includes a first facility, a utility, and a second facility running as processes on the protocol converter. The first facility communicates first data to the utility, the utility translates first data into second data, and the second facility communicates the second data to the host.
Important technical advantages of the present invention include a protocol converter with a modular design to adapt quickly and efficiently to new and changing communications protocols. This modular design is provided by software processes called facilities and utilities. A facility provides support for a specific link layer communications protocol, whereas a utility provides translation between higher level protocols. In a particular embodiment, utilities may be cascaded to provide layered protocol support.
Another important technical advantage includes managing the communications between facilities and utilities. In one embodiment, a communications subsystem maintains a process table having an entry for each process running on the protocol converter. In this manner, functions between utilities and facilities are isolated, process interfaces are clearly defined and robust, and the hardware/software interface in the protocol converter is accurately defined and reliably maintained. Other important technical advantages of the present invention include a session manager that spawns facilities and utilities, a logon subsystem, and a translator subsystem. Other technical advantages are readily apparent to one skilled in the art from the following figures, descriptions, and claims.